Classifier.



R. H. RICHARDS.

OLASSIFIER.

APPLICATION FILED 0016,1910.

Patented Feb. 23, 1915.

303m? H. RICHARDS, 0F BOSTON, SSACHUSETTS.

CLASSIETER.

Specification of Letters Patent.

Patented Feb. 23, 1915.

Application filed October 6, 1910. Serial No. 585,558.

To all whom it may concern Be it known that I, ROBERT H. RICHARDS, a citizen of the United States, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented a certain new and useful Improvement in Classifiers, of which the following is a specification.

This invention relates to classifiers for separating, grading or classifying materials such as ores, by the aid of Water and by what is known as hindered settling.

The object of the invention is to provide a hydraulic classifier simple in construction and efiicient in operation.

A more specific object is to break up lfaianks of sand tending to form in the classier. 1 In a receptacle" where sands are to be graded by hindered settling one must have a constriction at the bottom and a rising current of water in the receptacle. The

. contents of the receptacle will then be in the condition of quicksand, the heavier sands appearing at the top rapidly pass down through the quicksand and pass out through the spigot outlet at the bottom. The sands of medium weight contest with the quicksand already in the receptacle for the right to the place with the result that aportion of the quicksand may be displaced upwardly, a portion may be displaced down.- wardly, and a portion may maintain its place against the contestant. The lighter sands fail to penetrate the quicksandat all.

To facilitate such action it is preferable to have a weaker rising current in the upper part of the receptacle and a stronger rising current in the lower part of the receptacle;

but since some of the grains must descendand pass out through the spigot outlet below, there will be of necessity a neutral zone or layer of water current where the water neither goes up nor down. Below this neutral zone or layer the water flows down and out at the spigot. It is important thatthe' layer of maximum rising current should beas low as possible in the receptacle so as to give as great a height of hindered settling chamber as possible. In other words, the neutral zone or layer should be as low as possible.

The structure facilitating the favorable .oohditions for hindered settling is preferably one in which the receptacle is larger atfthe top and smaller at the bottom. The

wall of the receptacle is preferably perforated with numerous ports to admit water thereto from an annular chamber surrounding the wall. These ports are' preferably smaller in the upper part of the receptacle than in the lower, and fewer to the circle in the upper part than in the lower. The ports are preferably well distributed throughout the wall of the receptacle so that every part of the chamber may be attacked by correct- 1ng currents at all points, and in order to prevent the formation of dead banks where the sands are too hard, and chimneys where the sands are too liquidand active, When these banks form adjacent the wall of the receptacle they may be termed shell banks, and when they form in the center they may be termed core banks. The admission of water from the annular chamber through the Wall of the hindered settling chamber is designed to be such as to break up the formation both of the shell banks and of the core banks and also any downward adverse current that mightbe developed carrying down undesired slime. The ports accomplish' this object by acting systematically .Theports of the next layer below are radial,

and the next tangential, and so on alter nately all the way down.

The narrowing of thechamber downward and the enlarging of the holes near the bottom and their increasing number at the bottom, all tend .to increase the velocity of the rising current as the falling sands proceed until they approach the neutral zone or layer. Here the rising current suddenly slackens and stopsand below that point'it becomes a downward current for supplying the spigot outlet with water and sand.

A clear conception of one embodiment of the invention can be had by referring to the accompanying drawing in which like reference characters designate the same or similar parts in the several views.

Figure 1 is a' plan view of the classifier.

- the pockets of the classifier, the section being taken on the line IV-IV of Fig. 3.

he trough l of the classifier, see Figs. 1. and 2, has upwardly diverging sides. The feed end forms a hopper with the sides and with a deflecting or bafiie plate 2 spanning the trough 1 extending toward the bottom of the feed end and approaching same to within a short distance thereof, leaving a restricted passage 20 considerably below the water line 7, which permits the admission of material to the trough 1. The battle plate 2' is vertically adjustable between cleats on the sides of the trough, this adjustment being made possible by loosening the wedges 3 between the baffle plate and the cleats.

The overflow trough 5 at the discharge end of the trough 1 determines the height of the water line 7. A drain pipe 6, which is normally closed by a plug 21, extends outwardly from the lower portion of the discharge end of the trough 1, which end is inclined inwardly at the bottom. The bottom of the trough 1 slopes downwardly toward the discharge end and has attached thereto a series of vertical pockets 100. The

pockets 100 are cylindrical in shape with squared portions for connectlon to the bottom of trough 1. The pockets 100 are constructed in two main parts, an inner cone portion 4 forming a receptacle, and an outer cylindrical portion 10. Each cyllndrical portion 10 has an inlet opening 9 leading into the lower portions thereof. Each cone portion 4 has screw threads formed on the outer portion of its lower end for connection concentrically to the bottom of the cylindrical portion 10, which bottom is formed with a hexagonal boss 19 pierced and threaded for said connection. The upper end of the cylindrical portion 10 abuts against a flange or lip formed on the upper projecting part of cone portion 4 forming annular chamber 16 between the walls of the cylindrical portion 10 and the cone portion 4. The cone portion 4 has a square opening 15 in its upper end to register with a similarly formed port 8 in the bottom of the trough 1. This square opening gradually merges into the circular interior of the cone portion 4 but the circular interior of the cone portion 4 extends the entire length of the cylindrical portion 10- when the parts are assembled. Radial ports 11, 14, penetrate the walls of the cone portion 4, the upper and smaller radial ports 11 being few in number and widely spaced as compared to the lower and larger radial ports 14.

Tangential ports 12, 13, penetrate the walls of the cone portion 4 at planes alternating with the planes of the ports 11, 14. The upper and smaller tangential ports 12 are few in number and widely spaced as compared to the lower and larger tangential ports 13. The tangential ports 12, 13, entering the cone portion 4, are directed the same way as the inlet opening 9 entering the cylinder portion 10. The radial ports 11, 14, it will be seen are normal in horizontal planes to the wall of the cone portion 4. The bushing 17 is fastened concentrically into the lower end of the cone portion 4. A spigot 18 is screw threaded concentrically within the bushing 1'7, or an ordinary plug spigot, or a molasses spigot may be used. The size of the outlet may be varied by selecting a suitable spigot 18. The inlets 9 are connected by suitable piping for admitting water to the annular chambers 16. r

The operation is as usual in this type of machine. The materials are fed into the hopper at the baffle plate 2 and water is admitted to the several pockets 100 in desired amount and pressure. The heaviest particles pass through the first pocket, being separated from the remainder which pass on for separation by the next pocket of the heaviest of the remaining particles, and so on until slimes are delivered from the overflow trough 5. As already stated in the preliminary explanation hereinabove, the radial or centrally directed jets of water serve to break up the formation of core banks,

while the tangential or laterally directed jets serve to break up the formation of shell banks as also to maintain at all times a regular and uniform current throughout the horizontal area of each settling chamber. For reasons stated the neutral zone or layer is located in the lower part of the cone portion 4, thus giving a maximum size of hindered settling chamber above such zone.

It should be understood that it is not dewalls at an oblique angle in a horizontalplane, and means for delivering water into said receptacle through said ports.

2. In a classifier, a receptacle forming a chamber free from obstruction and having walls perforated by ports of which the upper are smaller in size than the lower, means for discharge of water and concentrates from the lower end of said receptacle, and means, free from direct communication with the discharge from said means, for delivering water into the receptacle through said ports.

3. In a classifier, a receptacle having walls 1,1ae,522 I perforated by ports of which the upper are fewer in number than the lower, and means for delivering water into the rece tacle through said ports, some of said ports eing directed along the surface of said walls and other of said ports being directed toward the mid portion of said receptacle.

4. In a classifier, a receptacle forming a chamber which is free from obstruction and having walls perforated by ports of which the upper are smaller in size and fewer in number than the lower, means for discharge of water and concentrates from the-lower end of said receptacleand means for delivering water into the receptacle through said ports.

5. In a classifier, a receptacle having up-z horizontal plane being less than the percentage of total port area in portions. of

said wall below said plane, means for delivering water into the receptacle through said ports, alternate ones of said ports being centrally directed to cause the water delivered therethrough to break up core banks and the remaining alternate ones of said ports being laterally directed to cause the water delivered therethrough to break up shell banks,'means for permitting the discharge of said water, and means for permitting the discharge of concentrates from said receptacle.

7. In a classifier, a receptacle forming a chamber which is free from obstruction and havingperforated uniformly upwardly diverging walls, a wall forming with said receptacle an annular chamber surrounding said receptacle and communicating with said first chamber through the perforations of said walls, the perforations of said walls and said annular chamber being spaced vertically along the major portion of said receptacle walls and said perforations being alternately centrally and laterally directed to respectively break up core banks and shell banks, an outlet means at the bottom of said receptacle and an inlet means to said annular chamber.

8. In a classifier, a receptacle having walls perforated by ports some of which penetrate the walls in a horizontal plane and are directed toward the mid portion of said receptacle and others of which penetrate the walls in a horizontal plane and are directed along said wall, and means for delivering water into the receptacle through said ports.

In testimony whereof, I aflix my signature in the presence of two witnesses.

ROBERT H. RICHARDS.

Witnesses G. F. DE WEIN, H. C. CASE." 

